As a process for producing aromatic compounds, such as benzene, and hydrogen from a lower hydrocarbon, particularly methane, one is known in which methane is reacted in the presence of a catalyst. As the catalyst upon this, molybdenum supported on a ZSM-5 series zeolite is said to be effective (Non-patent Publication 1).
However, even in the case of using these catalysts, it has problems that carbon is precipitated in a large amount and that conversion of methane is low.
In order to solve this problem, there has been proposed a catalyst in which a catalyst material such as Mo (molybdenum) is supported on a porous metallosilicate, as disclosed, for example, in Patent Publication 1 or Patent Publication 2. It has been confirmed in Patent Publication 1 and Patent Publication 2 that lower hydrocarbons are efficiently turned into aromatic compounds by using a catalyst in which a metal component is supported on a porous metallosilicate as a support having a micropore diameter of 7 angstroms, and along with this a high purity hydrogen is obtained.
Then, in Patent Publication 3 and Patent Publication 4, zeolite is chemically modified with a silane compound, prior to supporting a metal component, such as molybdenum, on zeolite, in order to improve selectivity and yield of the catalytic reaction.
That is, benzene selectivity has improved, and, since catalyst deterioration by coking is reduced, catalyst stability has improved remarkably, by conducting a molecular-level surface treatment, such as silane treatment, on zeolite (metallosilicate).